WordNet (r) 3.0 (2006):
appal v 1: strike with disgust or revulsion; "The scandalous behavior of this married woman shocked her friends" [syn: shock, offend, scandalize, scandalise, appal, appall, outrage] 2: fill with apprehension or alarm; cause to be unpleasantly surprised; "I was horrified at the thought of being late for my interview"; "The news of the executions horrified us" [syn: dismay, alarm, appal, appall, horrify]